Generously butter eight 3/4-cup soufflé dishes. Stir chocolate, butter, coriander, cardamom, cinnamon, cloves, and white pepper in heavy medium saucepan over low heat until melted and smooth. Cool slightly. Whisk eggs, egg yolks, and vanilla in large bowl to blend. Whisk in 3 cups powdered sugar, then chocolate mixture, then flour. Transfer batter to prepared dishes, filling to top and dividing equally. (Can be made 1 day ahead. Cover and refrigerate.)